Prior Art
This invention applies to statistical devices.
More particularly, this invention applies to medical statistical devices or devices using statistics in a medical environment.
More particularly, the invention applies to obtaining statistical information in control charts, for monitoring and analysis of medical processes.
Statistical analysis using Shehwart type process control charts was developed approximately 40 years ago in its present form. The use of statistics generally in medicine probably dates back to the early use of the scientific method in determining causes. Statistics are currently kept for purposes of disease control and diagnosis. The shortcoming of prior art in this area is not the failure to use accepted statistical techniques, but the failure to treat a medical patient as a true process. In any process, it is unacceptable to have an inflexible standard set because of the number of changes and steady states possible in any situation.
One example of statistical analysis in a medical environment is found in Bell, et al.; U.S. Pat. No. 3,322,954; which relates to diagnosis of statistically significant variations of radiation.
The use of inflexible standards in a statistical situation using central processing units is also known in the medical field. Hutchins; U.S. Pat. No. 4,583,524; processes information in order to obtain medical diagnosis or treatment. Hrushesky; U.S. Pat. No. 4,519,395; shows the use of statistically analyzed mean and standard error in heart rate. It foresees the monitoring of not only the patient, but the addition of drugs to the patient over time. Similarly, John; U.S. Pat. No. 4,545,388; shows the application of basic statistical computation of mean and variance and comparison to a previously obtained self norm for a given individual. Both of these patents substitute the use of statistically inflexible standards for medical judgment and provide signals relative to the change. Both fall short of the current invention by falling to provide for process charts and following the various stable states in the course of a patient's treatment. These patents substitute limited information to the information provided by Shehwart type process control charts which signify change over time and provide a continuous and monitorable statistical analysis.
Hrushesky and John address the broad aspects applicable to basic determinations of the idea of finding statistically significant changes in mean and standard deviation or variance measurements. Because neither use control chart tracking of a patient, the prior art patents are limited to situations where a known norm is available and where the patient is controlled only by attempting to reach the given norm.
The present invention allows for the variations necessary to follow a patient who does not have a norm, and perhaps never will, during the medical intervention process. The present method treats the patient as an ongoing process with the examination being directed to changes in the process and stabilizing or maneuvering the process in any given direction. The use of control charts allows the physician to set a given norm for a patient regardless of the patient's current condition or records kept on the patient.
The present invention addresses the question by giving a graphical analysis which is continuously monitorable by the physician and wherein the limits may be adjusted to allow the user to reset the analysis as a given patient changes.
Typical medical devices using current technology only give indicators or alarms of problems which show single events out of the ordinary when a patient's condition has already become unstable. Prior art was designed in order to have machines assist in the practice medicine for the doctor. Since medicine is a less than certain science, this results in equipment which does not serve a consistently useful function statistically.
Other existing equipment and methods provide a graph format but without statistical analysis, merely provide graphing of raw data. The present process allows for obtaining statistically significant historical analysis of the varying conditions, medicine, and equipment used for treatment.
One purpose of this invention is to provide a physician statistical information on a patient and to present the information in an interpretable form to a physician/statistician at a constant rate with sufficient statistical information being provided at one time to have statistical signicance.
Another purpose of the method is to provide an early warning system for medical patients. This process will enhance the early recognitions of problems with medical patients while being monitored with various equipment.
Another purpose is to provide an early warning system which will enable the physician to reduce the probability of the patient's going into unstable conditions. This process will also enable physicians to determine the stability of a patient for the process of discharging from hospital stay.
Another purpose it to provide a process with the capability to interface computers to medical devices. the process will use serial port communications from medical devices to a computer. The computer will then statistically analyze data received from the medical device and graphically display the statistical analysis of this data. This analysis of data will enable the physician or clinician to detect early indicators of non-stable conditions for the patient.
Another purpose is to provide for alarm systems based on an unknown patient; they are not individualized. The statistical analysis and graphics are based on an established normal for the individual. Mathematical laws and statistical formulas establish control limits for the patient based on the normal values for a particular patient.
Another purpose is to provide a method of statistical analysis which will provide statistically significant information about medical equipment and medications applied during the monitoring period.
These and other objects and advantages of the invention will become better understood hereinafter from a consideration of the specification with reference to the accompanying drawings forming part thereof, and in which like numerals correspond to parts throughout the several views of the invention.